The present invention relates to an apparatus for suppressing vibration, caused by wind, earthquake or the like, of a structure, such as architectural and civil structures.
The inventor proposed, as a sole or a joint inventor, various types of the vibration suppressing apparatus in copending U.S. patent application Ser. No. 07/042,365 filed on Apr. 24, 1987 entitled "DEVICE FOR SUPPRESSING VIBRATION OF STRUCTURE", U.S. patent application Ser. No. 179,438 filed on Apr. 8, 1988 entitled "METHOD FOR RESTRAINING VIBRATION OF A BUILDING AND STRUCTURE THEREFOR", U.S. patent application Ser. No. 07/186,394 filed on Apr. 26, 1988 entitled "METHOD FOR RESTRAINING VIBRATION OF A FLOOR AND APPARATUS THEREFOR", U.S. patent application Ser. No. 07/186,613 filed on Apr. 27, 1988 entitled "METHOD FOR RESTRAINING RESPONSE OF A STRUCTURE TO OUTSIDE DISTURBANCES AND APPARATUS THEREFOR", U.S. patent application Ser. No. 07/191,278 filed on May 6, 1988 entitled "METHOD FOR EFFECTIVELY RESTRAINING RESPONSE OF A STRUCTURE TO OUTSIDE DISTURBANCES AND APPARATUS THEREFOR", and U.S. patent application Ser. No. 07/196,325 filed on May 20, 1988 eniitled "DEVICE FOR SUPPRESSING VIBRATION OF STRUCTURE". The disclosure of each of these U.S. applications is incorporated herein by reference.
With recent developments of high strength materials and with rapid progress in both construction engineering and computer structure analysis, high-rise structures have become much more lightweight and flexible than conventional ones. Such lightweight and flexible high-rise structures have a tendency that the natural frequency and vibration damping factor thereof become smaller, and hence there is a possibility that various kinds of vibration unexpectedly occur with a large amplitude due to external forces caused by earthquake and wind. Thus, such vibration of these structures can give uneasiness to occupants therein and, further, may provide stress beyond an allowable limit to the structures.
In U.S. Pat. No. 4,226,554, issued on Oct. 7, 1980, Vandiver et al teach an apparatus for absorbing dynamic forces, caused by wind, wave or seismic excitation, on a structure, in which apparatus a liquid, contained in a tank mounted on a structure, reduces a dynamic response of the structure when the latter is vibrated. This type of vibration suppressing device may be used for solving the above mentioned problems. However, it has a drawback in that it takes a considerable space in a structure and hence has a rather low space efficiency.
Accordingly, it is an object of the present invention to provide an apparatus for suppressing vibration of a structure, which apparatus is compact in construction and is hence excellent in space efficiency as compared to the prior art vibration suppressing device. Thus, the vibration suppressing apparatus according to the present invention may be installed in a desired location of a structure.